Peter Foster is the Telegraph's US Editor based in Washington DC. He moved to America in January 2012 after three years based in Beijing, where he covered the rise of China. Before that, he was based in New Delhi as South Asia correspondent. He has reported for The Telegraph for more than a decade, covering two Olympic Games, 9/11 in New York, the 2004 Boxing Day tsunami, the post-conflict phases in Afghanistan and Iraq and the 2011 Fukushima disaster in Japan.

Royal baby: Why America, proud republic, swoons over our royals

When the prince was born yesterday, CNN's red ticker screamed the breaking news, just as if war had been declared or plague and pestilence descended.

I've been asking why – given 1776 and all that – America seems to get so excited about our Royal family.

The evidence of the Royal industry is everywhere you look. The glossies are full of speculation about names and mocked-up photo shoots using lookalike models, while the TV news reporters flannelled from their perches outside the hospital for days in the run-up to the birth, with ever more exasperated and exhausted correspondents gasping for snippets to relay back to their masters in Atlanta or New York.

It is Americans who will buy a significant proportion of the commemorative tat that retail groups estimate could be worth some $225m.

On the face of it, the devotion seems to contradict the proud Republican roots of this country, particularly as, in my experience, the most fervent US royalists are often to be found among the Tea Party types who wear tricorne hats and can recite the Declaration of Independence off pat.

So where does that soft spot come from?

Asking around, top of the list, is the simple American love of pomp and circumstance. The sun set on the British Empire some time ago, but America still has pretensions in that regard and looks back at the "mother country" with a secret, latent affection for the outward trappings of royalty.

Then there is the simpler "Disney effect". Since America rejected monarchy, runs this argument, "the only princesses we have are those pink and plastic ones that Disney produces". So when a real-life one comes along like Diana or the Duchess Cambridge, it's understandable that everyone swoons.

As an adjunct to that, there is that eternally fantasised (and some might say infantilising) American view of Britain which explains the runaway success of shows like Downton Abbey, which worryingly was loved even by Hillary Clinton – although we must presume that (unlike Sarah Palin) she was aware that it is the Prime Minister who authorised British forces to join the US invasion of Iraq, not the Queen.

A Whiggish friend acknowledges the love phenomenon, but can't hide a sneer at the prostrations of his fellow countryman in the face of royalty. "Diasporas are horribly conservative in all the wrong ways," he chides, "They embrace the stupidest symbols. If America fancies itself as the UK diaspora, which it does to a certain extent, then it makes a sort of sense."

Whatever the reasons, they are not new. As historians have shown, Americans were following the fortunes of the Royals long before Twitter and CNN were around. They fascinated over Queen Victoria's coronation in 1838 and turned out in droves for the royal visit of her son, 18-year-old Albert Edward, Prince of Wales, in 1860.

Personally I can't help but side with my Whiggish friend and feel a twinge of disappointment that America, the country of perpetual rebirth and revolution should fall quite so helplessly for all this nostalgia and schlock, but then, in these hard times, we Brits can't afford to be sniffy about all those extra tourist dollars that will soon be raining down on London, so I shan't say it too loudly.